| Abstract: | An article that includes a fluorescent composition having at least one of
a fluorescent sensor compound and organic reporter molecules encapsulated
in a microsphere structure. When encapsulated, the fluorescent sensor
compound and the organic reporter molecules are distributed in a liquid
organic matrix. When non-encapsulated, the remaining one of the
fluorescent sensor compound and the organic reporter molecules reside in
the matrix. In response to a force applied to the composition sufficient
to break at least a portion of the microsphere structure, the fluorescent
sensor compound and the organic reporter molecules are transformed into a
non-reversible fluorescent state exhibiting a quantum yield greater than
0.2. The fluorescent state is objectively visually verifiable without
physically contacting the composition. |